I'm building a pen lathe

[Nevadablue]

I decided to build my own pen lathe based on Unimat 1 components. These little machines have a bad reputation, but I managed to get a lot of parts off of ebay and have been impressed so far with the quality of the parts I intend to use. I first got a few of the aluminum 'bed' extrusions, just for the feed screws and other parts. After I studied them for a while, I decided to get more components and build my own version of a pen lathe from them. I managed to get a large box of components, including two LONG bed parts.
I probably won't use the motor at all. I've ordered a sewing machine motor and speed control and a pair of flanged pillow block bearings. I intend to mount the sewing machine motor and build a jack shaft using the flanged bearings. This will allow me to use the lathe at any reasonable speed with sufficient power I think. I do have a Unimat SL lathe and Unimat SL lathe made into a dedicated milling machine. The mill is driven by a sewing machine motor and it works fine.
So, I found the headstock on the Unimat 1 to be surprisingly rigid and the bearings are good. The thread on the spindle is 12mm x 1 which is the same as the Unimat SL, so all of my accessories for those machines will work on this one. I'm making a drive pulley from aluminum. The metal is coming from a salvaged diesel engine piston. I like pistonium for parts, the price is right. I will probably use regular Unimat silicone belts for this machine so they interchange with my other machines.
So, here's the little machine sitting on the day bed in our living room. I bet you can't put your lathe on the couch!

The vertical column may end up just being a lamp stand, I'm not sure yet if I will attempt to make a drill press out of it.

 

[Nevadablue]

Oh, I almost forgot... the pen mandrel is one I bought for my larger wood lathe. I discovered that the adapter it came with just screwed off and then the shaft fits into one of the collets I got with the parts. So far it looks perfect! Now if it works as good as it looks. I'll also be building a nicer tool rest.

 

[Penpal]

Hi Ken you could easily use the metal lathe tool rest and use tool steel cutters etc. Make your own version of a live centre and mandrel saver combined I can help with pics as I have two Taig lathes I have modified.

Peter.

 

[Nevadablue]

Thanks Peter. I am interested in the live center/mandrel saver. I enjoy making parts and this one will be fun I'm sure.
Ken

 

[wm460]

A very interesting project Ken, I will follow this with interest.
How thick is the diesel engine piston?

 

[bassethound]

That lathe would fit in with Vic and the two dogs in he's chair! Very nice little tool indeed, love it

 

[Vic Perrin]

I have plenty of room for one of them It looks great

Vic

 

[Penpal]

Home made live Centre and Mandrel Saver

two Mandrel Savers one conventional lathe and another for the Taig Lathe.

For the Taig turned a brass piece same thread as the tail stock thread bored out to sleeve a bearing facing the lathe, made a brass insert the snug fit for the mandrel.

The conventional lathe one a mate made me from tough steel a live centre I made the brass insert with a snug fit to the mandrel note a temporary screw till I got an allen locking screw for it. These go backnearly ten years ago.


Peter.

 

[Penpal]

One of my Taig Lathes

With the mandrel fitted.THe winder for the tool rest part of a 35mm projector the stupid hand crank was too small.

Peter.

 

[Grump]

Been there done it sold it, the only way forward with old hands is cnc it init?

 

[paulm]

A very nice effort there Ken, love it

 

[Bill Mooney]

A very nice little lathe Ken. I have a Unimat which I've been using since 1975 & is still going strong.
Well we've moved on from pics on the carpet to pics on the couch.

 

[Jim]

I like the ingenuity that you have put into making this Ken .. Look forward to seeing some of it's work ..

 

[Dalboy]

I had one of them Ken could not get on with it ended up selling it. Hope the new motor helps

 

[Nevadablue]

Mark, I haven't drilled the center hole in the piston top yet, but I think it is about 3/4" thick. I'll get some pics when I get home. My wife and I are full time caregivers for our disabled Veteran son (Iraq War), and we are now on our monthly LONG trip to Salt Lake City for his treatment at the VA. sigh... Anyway, I have a collection of those old pistons. A pair of them are part of a long term project (all my projects seem long term ) to make an indexer setup for my larger mill. It will be kind of a headstock/tailstock thing, with the wrist pin bores being the headstock and tailstock bores.
Peter, thanks for the ideas, I'll have to see what parts I can scrounge for that. My Unimat lathe (both mill and lathe are actually Db200s, not SLs as I said) had quite a few modifications including a Taig tailstock.

And, here's the motor setup on the mill. I think the pen lathe will have a countershaft, if it works out.

Jim and Derek, I have hopes for the little lathe. I don't intend to push it hard, so it should do the job for me. I hope...

Oh, I cut a chunk of Lilac from one of my lady's plants... with permission of sorts. :nonono: I read yesterday that I should slice it in half and chunks, and seal the ends. Gotta do that I guess.

 

[Penpal]

Ken the best for your trip and treatment for your son in SLC.

Noted the Taig tailstock so my mods for mine will make perfect sense to you. Envy your mill device that should yield easily indexing plates. We are LDS so we are familiar with Salt Lake our daughter who arrived here yesterday from Logan Utah or one of the four in her family continually depart and arrive at SL Airport.

Kind regards Peter.

 

[Nevadablue]

Thanks Peter. We made it home safely today. Mike's (my son) treatment went well. We are all tired but happy to be home. I had a couple of packages waiting... The motor for the lathe arrived as well as some spare parts including another headstock. I couldn't get the drive pulley off of the headstock and didn't want to risk breaking it (too tired to think well), so I mounted it on the lathe. The motor went on like it was meant to be... jury rigged, but it WORKS! I'll make a proper mount for it later. This was just a test. The lathe is solid, stable, quiet and has plenty of power. I managed to make a bit of square stick into round stick without breaking anything. A very dull piece of crap gouge on a too-low tool rest but it made chips fine. I vacuumed up the dust before SWMBO saw the mess.
I won't really need the counter shaft but I will make and install it. I don't like the motor stuck way out on the end of the lathe. The counter shaft will allow it to be farther away from the dust too.

That long cross feed that is now holding the tool rest will become part of the dedicated pillar drill. I plan to mount it on the back side of the upright pillar and make that into my drill for blanks. I bought some aluminum and a hand screw too. The hand screw will get V cuts in each side to hold the blank for drilling. More on that later, but this will be a neat little, compact work unit I think. It may be a while until I get it finished, but it will be worth the effort it appears.

 

[Penpal]

Pleased to hear of your safe return with the family I fitted a 1/3 HP motor to my Taigs and put a shield behind the lathe to protect the motor it works great. Keep it up I am following closely.

Peter.

 

[wm460]

I like your modification to the tail stock, Am thinking of ideas to do that on both Vicky and my metal lathe.

What did you get the pistons out of?

 

[Nevadablue]

Thanks! The pistons are out of a Deutz engine. I saved several thinking of using them as raw material for casting, but now they have turned out to be useful in other ways.
I think I have the configuration for the Unimat 1 worked out. I've juggled the parts a dozen times and this seems to work. I'll make pulleys that are similar to the Unimat DB200 motor pulley I think. I found a chunk of 2" round aluminum stock in the shop today, so I think I'll make a few of this type of pulley:

Picture borrowed from an ebay ad. That is the intermediate pulley setup for a DB. I just need to make pulleys like that, but to fit the shafts on the Unimat 1.